Well, normally with a 7 year old thread I wouldn't bother resurrecting, but since it's already been recently brought back from the dead...
If so, you think it would be simple enough to wire any two pickup bass to do the same thing, right? Why not have your J bass do this?
I can see that... Perhaps other effects on the bridge p'up...
If this arrangement is so cool, why for aren't more guys wiring their J basses this way, I wonder - because it DOES sound kinda cool...
This is correct, you can wire any two pickup bass this way, as long as it also features two vol and two tone controls (by my understanding, otherwise the single tone control on a jazz defeats the possibility). I've posted it a number of times, but in case you haven't seen it, I actually performed a similar rewiring on my Jazz Bass.
My wiring isn't quite as elegant as a Ric-O-Sound setup, but essentially the bass now has two separate circuits. The neck pup goes to one stacked pot of vol/tone, and then to its output. The bridge pickup does the same. In my case, this came both from seeing other basses with stereo wiring (Berry Oakley used it, Chris Squire, Geddy Lee, etc) as well as what I saw as out of necessity. The Dagstar pickup has way more output than the jazz, and sending them both through a single mono output, mixed together, wasn't going to cut it. I needed the option of EQing and boosting the volume of the jazz pickup to get it on the same level as the Dagstar (which sounds best wide open, so rolling it off wasn't really an option in my mind). Secondly, the whole reason I bought a stack knob jazz in the first place is to have the ability to set each pickup with different tonal settings. However, the RI '62s don't have the cap as in the originals that makes this possible (it also rolled off high end, so I didn't really want to put it into the circuit anyways), so the tone controls interact, sort of negating the whole point of the stack knobs.
Now on to the practical application. First to recording: this is where it really shines, IMO, since you can simultaneously record two bass tracks. You can them separate them in the stereo field and add different EQ and effects and don't have to retrack the line (although, I guess nowadays you could just duplicate the line digitally, copy/paste what not). For playing live, I also find it very useful. If I'm using a one amp rig, I'll run one pup into the bright channel and the other into the normal channel on my Sunn 2000s. Most often this has been neck into bright, and bridge into normal, as this helps normalize the output discrepancies somewhat, though I've been switching up recently, which also sounds really good. However, if I can get away with it, I really like the dual-rig set up. In this instance, I'll send the neck pickup into a Sunn 2000s, and the bridge into a Sunn 1200s. I can then put different effects on different pickups (fuzz into one, phaser into another, keep one dry, etc), and often I'll put reverb or trem on the bridge pickup to add some subtle depth to the sound. Does the audience notice? Idk, but they definitely notice the 2 amps and 2 2x15s

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